120d very sluggish & air/vacuum leak noise!

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Manufactured from 2004 to 2013

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aaronblack
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120d very sluggish & air/vacuum leak noise!

Post by aaronblack » Sat Jul 21, 2018 7:33 pm

Hi all,

New member here, came over from a E93. A few problems with my 120d which I think might be correlated

1 - Over the past few weeks I've realised a lack of power throughout the entire rev range. Even at 3/4/5k RPM it still is very very sluggish and probably takes a good 10 seconds to get to 40mph under normal driving conditions.

2 - At and above 1k RPM, when I put my foot down I hear a very loud/noticeable vacuum/air leak from the left front engine bay behind the dash. This isn't apparent if I'm cruising at a constant speed, however anytime the car is 'accelerating' you could hear it.

3 - And finally i've recently started to feel a bit of smoke inside the cabin...


Now the chain kit has been done around 6months ago, so i highly doubt the onise is the chain. I've even recorded the engine at idle and listed to it with headphones and am pretty sure it isnt the chain.

I am just not sure if its EGR, turbo actuator, exhaust leak? Any help is very much appreciated :)

Dave2032
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Re: 120d very sluggish & air/vacuum leak noise!

Post by Dave2032 » Sat Jul 21, 2018 9:30 pm

Does it sound like a rush of air?

Turbo hose split or where the hose joins another bit of hose/pipe has separated????


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Bimmer112
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Re: 120d very sluggish & air/vacuum leak noise!

Post by Bimmer112 » Sun Jul 22, 2018 2:54 pm

Check your hoses and connections. I had the same problem when I didnt put intercooler hose all the way in after cleaning.. Try to locate where the sound is coming from exactly - put the car in neutral and have someone press the throttle while you are listening in the engine bay.
BMW e87 118d M47N2
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aaronblack
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Re: 120d very sluggish & air/vacuum leak noise!

Post by aaronblack » Sun Jul 22, 2018 7:31 pm

Thanks for the advice. I took out the airbox, turbo intake and checked the inter cooler connections on both ends and it all appeared to be connected correctly with only slight play at the ends, not sure if this could have such impact!

The turbo had some slight oil leaking nothing major. All other hoses and pipes seem to be in good condition too.

I may have to take the bumper off and start disconnecting all the tubes 😑

aaronblack
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Re: 120d very sluggish & air/vacuum leak noise!

Post by aaronblack » Sun Jul 22, 2018 7:34 pm

On another note, it has a Essex turbo which I’m not sure is the original? Meaning it possibly has had a turbo replacement sometime in the past.

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